Albums that start out magnificently, then trail off.

I actually prefer the first half of Filosofem as well, but I have no issues with the second half.
 
The first half of Burzum is of course "easier listening", and it more suitable for everyday purposes, but the second half is quite magical when you're in that sort of mood.

And "Spell of Retribution"? What the hell? The last four tracks are all GREAT!
 
AMON AMARTH - Versus the World

First half >>>> second half

1000 Years of Oppression disagrees.

Forbidden - Forbidden Evil. "Chalice of Blood" and "Though Eyes of Glass" are amazing, the title track is one of the greatest thrash songs ever, and then the second half of the album is just completely forgettable and worthless.

Totally agreed on Falkenbach. "Vanadis" utterly blew me away the first time I heard it, I could not think of anything more awesome at the time. Then I listened to the rest of the album and sorta fell asleep.